Wildfire smoke a health risk for millions

LOS ANGELES — Wildfire smoke poses a growing health risk to millions of Americans, even for those who live hundreds of miles from the flames, a new report by an environmental group says.

About two-thirds of Americans, or nearly 212 million people, lived in counties that two years ago contended with wildfire smoke linked to respiratory problems such as asthma, pneumonia and chronic lung diseases, according to a report released by the Natural Resources Defense Council.

The group used satellite imagery of smoke plumes from the 2011 wildfire season — one of the worst in recent years — to take a nationwide snapshot of air quality. The analysis found that the extent of the country affected by wildfire smoke was 50 times greater than the area burned in the fires.

It’s no surprise that many of the smokiest states had major blazes that year. That includes Texas, which topped the list with more than 25 million people living in places with air fouled by wildfires for a week or more, followed by Florida and Georgia.

But six of the most affected states, including Illinois, Missouri, Iowa and Kansas, experienced more than a week of medium- to high-density smoke even though they had no major fires, the report found. That’s because smoke drifts far downwind of fire perimeters, spreading health effects across state lines.

Some of the most harmful components of wildfire smoke are fine particles, which can lodge deep in the lungs and lead to a host of respiratory and cardiovascular problems. Particularly vulnerable are children, the elderly, pregnant women and people with heart disease and other conditions.

In one study cited in the report, University of California, Irvine researchers found that Southern California’s 2003 wildfire season resulted in 69 premature deaths, 778 hospitalizations, 1,431 emergency room visits and 47,605 outpatient visits.